In recent years, high-performance mobile information display terminals (hereafter referred to as mobile devices) such as smartphones have been introduced and used for various applications. One of such applications is the use of a mobile device to control a home appliance. As compared to a laptop computer, a smartphone, a tablet, or the like has a form that does not need to coincide with a posture of its housing, and can be held freely in any of the orientations including portrait, landscape, and upside-down. This raises the need to display a GUI in an orientation required by a user.
There is a mobile device product that is implemented to detect a gravity direction and display a GUI so that a side situated uppermost in a vertical direction with respect to the ground corresponds to the top of the GUI. However, since the user holds the mobile device in various ways, this technique cannot be applied to cases such as when the user rotates the mobile device while holding it in a horizontal position.
A method for solving this problem is disclosed in Patent Literature (PTL) 1. PTL 1 discloses a method of detecting, based on a pressure sensed by a touch sensor, whether the mobile device is held with a single hand or both hands, and changing the screen display depending on the detection result.